Accessing root Angular 2 injector instance globally

Question

How to access an instance of root Angular 2 injector globally (say, from browser console).

In Angular 1 it was angular.element(document).injector().

Answer 1

In Angular v.4.x.x the root injector is located on the PlatformRef. You can access it like this:

import {platformBrowserDynamic} from '@angular/platform-browser-dynamic';

// create a platform    
let platform = platformBrowserDynamic();

// save reference to the global object
window['rootInjector'] = platform.injector;

// boostrap application
platform.bootstrapModule(AppModule);

Or inside any component like this:

export class AppComponent {
  constructor(platform: PlatformRef) {
      console.log(platform.injector);

But the root injector is pretty useless. It contains mostly compiler and platform specific data and helpers:

[
  "InjectionToken Platform ID",
  "PlatformRef_",
  "PlatformRef",
  "Reflector",
  "ReflectorReader",
  "TestabilityRegistry",
  "Console",
  "InjectionToken compilerOptions",
  "CompilerFactory",
  "InjectionToken Platform Initializer",
  "PlatformLocation",
  "InjectionToken DocumentToken",
  "InjectionToken Platform: browserDynamic",
  "InjectionToken Platform: coreDynamic",
  "InjectionToken Platform: core"
]

You're probably looking for AppModule injector which you can get like this:

platform.bootstrapModule(AppModule).then((module) => {
  window['rootInjector'] = module.injector;
});

You can extract ApplicationRef or root ComponentRef from it:

platform.bootstrapModule(AppModule).then((module) => {
  let applicationRef = module.injector.get(ApplicationRef);
  let rootComponentRef = applicationRef.components[0];
});

Also, if Angular is running in the development mode, you can get either AppModule or lazy loaded NgModule injector like this:

ng.probe($0).injector.view.root.ngModule